The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Electronic fuel injection is a known method for fuel delivery in compression-ignition and spark-ignition internal combustion engines. A fuel injector can be a solenoid-actuated or piezo-electric valve device mounted on an engine and positioned to deliver pressurized fuel into a combustion chamber of an engine cylinder. Each injector is preferably energized during each combustion cycle for a period of time, i.e., injection duration, determined based upon pre-calibrated parameters for engine operating conditions. Multiple fuel injection events can occur each combustion cycle for each cylinder.
Known fuel injectors have linear and non-linear regions of fuel mass delivery with respect to injection duration. The linear regions of fuel mass delivery include commanded injection durations, having corresponding known and unique fuel mass deliveries at a predetermined fuel pressure. Linear regions of fuel mass delivery include regions whereat fuel mass delivery increases monotonically with increased injection durations at constant fuel pressure.
The non-linear regions of fuel mass delivery include commanded injection durations having unknown or unpredictable fuel mass deliveries at a predetermined fuel pressure, including non-monotonic regions whereat the fuel injector can deliver the same fuel mass quantity at different injection durations. Boundaries of the linear and non-linear regions may vary in different fuel injector systems.